As people we often give others gifts for many reasons like for a special occasion, to show appreciation, to thank someone, or to get their attention. Similarly, many animals also give gifts for reasons just like ours. One animal that gives an especially cool gift is the spotted bowerbird. In this species, male bowerbirds spend days crafting a complicated tower made of stickers, feathers, and rocks called a bower and performing dances around it in order to attract a female mate. Think of it like you worked really hard on a homemade gift for a friend’s birthday but performed a dance around it before you gave it to them.
On top of making a bower and dancing there is one more part in their gift giving ritual: competition. The adult males that build bowers often have to defend them from other adult males who also want the female’s attention. The owner of a bower will often allow younger male birds called subordinates to hang around their bowers because they don’t see them as a threat. Like when you let your younger sibling hangout in your room. It has even been suggested that the younger males learn from watching the adults create the bowers and dance. This led scientists to question if young males were less skilled at performing than adults and if the presence of the young males benefits either of them.
The scientists answered these questions by watching the behavior of young and adult wild spotted bowerbirds. They took videos of 14 different bowers and owners over the course of multiple years and watched how the adult bower owners and the young males interacted with each other. They predicted that the young males would be worse at performing than the adults because they would have worse motor skills and not as much experience. They also predicted that both the adults and the young males would benefit from each other. After watching the videos and determining their results the scientists found out their predictions were only half right.
Surprisingly, the young male bowerbirds had the same motor and performance skills as the adults, which the scientists did not predict. On the other hand, they did find that the presence of young males at an adult’s bower benefits both of them. The adult males with more young males at their bower suffered less attacks from other adult birds and had better luck attracting females. While the young males benefit by becoming the adult bird’s “next in line”. This means that the young males can take ownership and use the adult’s bower when they are not there and gain dominance over other males in the area. Based on these findings the scientists concluded that male bowerbirds form coalitions which is a fancy word for friendships during mating season. This conclusion is especially exciting because this is new information in science. Before the work by these scientists was done nobody knew that male bowerbirds formed friendships to help each other like this. Animals are often much more similar to us than we think!
Reference
Spezie G., Fusani L. (2022) Male–male associations in spotted bowerbirds (Ptilonorhynchus maculatus) exhibit attributes of courtship coalitions. Behavioral Ecology and Sociobiology 76:97 https://doi.org/10.1007/s00265-022-03200-x
